BERLIN -- European nations are not doing enough to fight climate change and should show more leadership before they criticise the United States and Asia, the head of the U.N. Environment Programme (UNEP) said on Saturday.

Achim Steiner said in an interview with Bild am Sonntag newspaper that climate change has been caused primarily by carbon dioxide emissions from Western industrialised nations and it was thus their responsibility to lead the fight against it.

He said the United States and Asia were now moving faster in the fight against climate change than Europe, which he said has grown complacent.

"The Americans and Asians are catching up quickly and are becoming strong business competitors (with green technologies)," Steiner said, in excerpts of the interview released ahead of Sunday's publication.

"But in Europe we've cherished the illusion in recent years that 'we've done enough'," he added.

He praised Germany, which holds the European Union presidency, for "showing initiative" but said it was not enough.

"It's important that Germany move forward," he said, referring to Europe's biggest emitter of greenhouse gases.

The European Union's environment commissioner earlier this month said Germany's lack of progress in cutting greenhouse gas emissions was holding back international efforts to combat global warming.

Chancellor Angela Merkel has vowed to make fighting climate change a centrepiece of Germany's twin EU and G8 presidencies.

But Germany's recent track record on cutting carbon dioxide emissions is poor. It vowed to cut these by 21 percent from 1990 to 2012 under the Kyoto Protocol but has slipped away from the target.

"Yes, we favour ecology and responsibility for the future, but let us stick to what we can do," said Kurt Beck, chairman of the Social Democrats who share power with Merkel's party, in a speech on Saturday. Beck has opposed more ambitious CO2 cuts.

"Let's stay reasonable, yes, but let's use our technology worldwide so that other countries can grow with less CO2."

DON'T BLAME CHINA

Carbon dioxide (CO2), produced by burning fossil fuels, traps heat in the atmosphere. Scientists say if emissions are not curbed sea levels will rise, while drought and floods will have more dire consequences.

The European Commission last month presented a new more ambitious target of cutting CO2 in the 27-nation bloc by at least 20 percent by 2020 from 1990 levels with the possibility of going to 30 percent if other developed countries joined in.

Steiner also said it was a myth for Europeans to think China had no interest in the environment.

"We have a historic responsibility," Steiner, a German national who was born and raised in Brazil, said when asked why Europeans should cut CO2 emissions when "hundreds of millions of Chinese were switching from bicycles for cars."

"The climate problem of today was not caused by China but above all by Western nations. So the first step has to come from us. Moreover, it's wrong to assume that China is not interested in climate protection."

Steiner pointed out that the Chinese government last year launched a $180 billion renewable energy programme.

"We've only been looking at China through brown smog coloured glasses," he said. "But there are already cities being planned (in China) that will have zero CO2 emissions."